La Via Romana, or the "Roman Way" is the series of virtues that were established in Ancient Rome with the purpose of building the true male specimen and the model Roman citizen. The medium through which these virtues were established was the strong belief and admiration that Romans bestowed upon their deities, whether it was Osisis, Dyonisus, or Attis.
The aspiring citizen would embrace the following behaviors to build himself in to an outstanding individual. They include
- Dignitas- dignity
- Firmitas - firmness of character
- Comitas- committment
- Clementia- forgiveness
- Salubritas- wholesomeness
- Frugalitas- common sense in finances
- Humanitas - humanity
- Honestas - honesty
- Pietas - mercy
- Industria - industry
- Prudentia -prudence
There are more virtues still, but the idea behind these builing blocks of civilization were mainly to build ourselves after our betters, those "betters" being the divine beings that watch over us, whether it was one or more gods.
In the movie, we find that Maximus's natural instinct was to tap on each and every one of the Roman virtues which, in the eyes on the emperor, made Maximums into a human godlike figure, that is, someone whose gravitas (leadership and earnestness) and auctoritas (spiritual strength) were so strong that it seemed as if the supernatural forces handed him such gifts for the purpose of ruling Rome.
So evident is this in the story of Maximus that the emperor even bypasses his own son, Commodus, to inherit his duly righteous claim to the throne and, instead, bestows it upon Maximus.
Perhaps this gravitas is more evident in Maximus's famous words:
What we do in life echoes in eternity
which is a strong manifestation that shows both gravitas and auctoritas at its best. The fact that Commodus usurped the rightfully-earned title of emperor from Maximus and dropped him down to the rank of a Gladiator and slave- killing his wife and son in the process- makes Maximus all the more dignified as a human being and seeing how he literally faced death in the face and continued with his goal in life, which in this case was to avenge the injustice perpetrated against his family, denoted a level of personal strength and spiritual leadership that cannot be replicated.
My name is Maximus Decimus Meridius, commander of the Armies of the North, General of the Felix Legions, loyal servant to the true emperor, Marcus Aurelius. Father to a murdered son, husband to a murdered wife. And I will have my vengeance, in this life or the next
are also a reflection of the cult of Mithraism, practiced mostly among Roman soldiers. This cult claimed that Mithras was the embodiment of goodness (sort of a Jesus-type figure) that renewed life, and if he manifested itself in human form and died, he would renew himself as well. The "in this life or the next" comment as well as the "echoes in eternity" phrase are meditations born out of Mithraism and the military cult of Mithras who, it can be concluded, was the protector of the soldiers in battle.
I am including with this answer a link to a very detailed resource on the historical sources from which the movie Gladiator was drafted.